Department of Zoology, Sri Krishnadevaraya University, Anantapuramu, 515003, India; Department of Zoology, D.K. Govt. Degree College for Women (Autonomous), Dargamitta, Nellore, 524003, India.
Department of Zoology, Vikrama Simhapuri University Post-Graduation Centre, Kavali, 524201, India.
Chemosphere. 2020 Jun;249:126148. doi: 10.1016/j.chemosphere.2020.126148. Epub 2020 Feb 7.
Cypermethrin is one of the widely used type-II pyrethroid and the indiscriminate use of this pesticide leads to life threatening effects and in particular showed developmental effects in sensitive populations such as children and pregnant woman. However, the molecular mechanisms underlying cypermethrin-induced development toxicity is not well defined. To address this gap, the present study was designed to investigate the phenotypic and transcriptomic (next generation RNA-Seq method) impact of cypermethrin in zebrafish embryos as a model system. Zebrafish embryos at two time points, 24 h postfertilization (hpf) and 48 hpf were exposed to cypermethrin at a concentration of 10 μg/L. Respective control groups were maintained. Cypermethrin induced both phenotypic and transcriptomic changes in zebrafish embryos at 48 hpf. The phenotypic anomalies such as delayed hatching rate, increased heartbeat rate and deformed axial spinal curvature in cypermethrin exposed zebrafish embryos at 48 hpf as compared to its respective controls. Transcriptomic analysis indicated that cypermethrin exposure altered genes associated with visual/eye development and gene functional profiling also revealed that cypermethrin stress over a period of 48 h disrupts phototransduction pathway in zebrafish embryos. Interestingly, cypermethrin exposure resulted in up regulation of only one gene, tnnt3b, fast muscle troponin isoform 3T in 24 hpf embryos as compared to its respective controls. The present model system, cypermethrin exposed zebrafish embryos elaborates the toxic consequences of cypermethrin exposure during developmental stages, especially in fishes. The present findings paves a way to understand the visual impairment in sensitive populations such as children exposed to cypermethrin during their embryonic period and further research is warranted.
氯菊酯是广泛使用的 II 型拟除虫菊酯之一，这种杀虫剂的滥用会导致危及生命的影响，特别是对儿童和孕妇等敏感人群表现出发育影响。然而，氯菊酯诱导发育毒性的分子机制尚不清楚。为了解决这一空白，本研究旨在使用斑马鱼胚胎作为模型系统，研究氯菊酯对其表型和转录组（下一代 RNA-Seq 方法）的影响。在受精后 24 小时（hpf）和 48 小时（hpf）两个时间点，将斑马鱼胚胎暴露于 10μg/L 的氯菊酯中，相应的对照组保持不变。氯菊酯在 48 hpf 时诱导斑马鱼胚胎出现表型和转录组变化。与各自的对照组相比，48 hpf 时暴露于氯菊酯的斑马鱼胚胎出现孵化率延迟、心率增加和轴向脊柱曲率变形等表型异常。转录组分析表明，氯菊酯暴露改变了与视觉/眼睛发育相关的基因，基因功能分析还表明，氯菊酯在 48 小时内的应激会破坏斑马鱼胚胎的光转导途径。有趣的是，与各自的对照组相比，氯菊酯暴露仅导致 24 hpf 胚胎中 tnnt3b 基因，即快肌肌钙蛋白 3T 的上调。本研究中的模型系统，即暴露于氯菊酯的斑马鱼胚胎，详细阐述了在发育阶段暴露于氯菊酯的毒性后果，特别是在鱼类中。本研究结果为了解儿童等敏感人群在胚胎期接触氯菊酯时出现视力障碍的原因铺平了道路，需要进一步研究。
